1. Field of the Invention
The invention relates to spark plugs and more particularly to the electrodes of spark plugs and methods of making a spark plug electrode with a noble metal.
2. Description of Related Art
Internal combustion engines utilize spark plugs to ignite a compressed mixture of air gasoline. Each spark plug includes a portion disposed in a cylinder of the engine; the portion including two electrodes spaced from one another. A voltage is applied across the two electrodes, resulting in a spark that initiates combustion. In operation, charges of up to about 40,000 volts may be applied through the spark plug center electrode, causing a spark to jump the gap between the center electrode and the opposing ground electrode. Due to the very nature of an internal combustion engine, spark plugs are exposed to extreme conditions in operation, such as high temperatures and pressures, as well as corrosive combustion gases.